Burn-In

Definition - What does Burn-In mean?

Burn-in is permanent discoloration which can occur on areas of an electronic
display. Burn-in often occurs in cathode ray tube displays,
especially ones based on older CGA and EGA CRT technology; this is due to
the cumulative non-uniform usage of pixels. Methods such as screensavers
and switching off the display when not in use are used to prevent burn-in.

Techopedia explains Burn-In

Burn-in usually occurs when
a non-moving image is displayed on a monitor for a long period of time. This results
in the burning of phosphors in the monitor, with the image often faintly visible
even after the display is switched off. Burn-in occurs due to the light-emitting pixels decaying over time, losing their coherency and color accuracy.
The effects of burn-in are immediate and cause continual degradation of image quality.

The length of time
required for burn-in to set in depends on a number of factors such as the quality
of the phosphors used in the display, the amount of time used to display images and the
degree of non-uniformity of sub-pixel usage. Modern displays are less susceptible
to burn-in, as
they have features developed to minimize the issue. One such feature commonly
used is known as pixel shifting, which shifts the image on the screen so that
pixels are frequently refreshed and changed. Turning off the monitor when not in use as
well as use of screensavers in the case of computer displays can also help in minimizing
the risk of burn-in.